High stability Altimeter SysTem for Air data Computers
EC Contract No.: AST4-CT-2005-012334 Thematic priority: Aeronautics and Space Coordinator: SINTEF, Norway
The project responds to the challenge of ensuring that, irrespective of the growth of air traffic, air transportation will be safer. HASTAC contributes to one of the major challenges identified in the Strategic Research Agenda for European aeronautics.
HASTAC will contribute to improved safety in different flight situations:
On board technologies for prevention of controlled flight into terrain
On board technologies for in-flight and on-ground collision avoidance novel concepts
Techniques enabling the development of improved aviation safety metrics '
Development in the different work packages
The main project strategic objective is to increase the safety in all in-flight situations, particularly low visibility situations, by improving the transducers used in Air Data Computers (ADC) for aircraft applications.
The results are relevant in auto pilot situations in the reduced vertical separation minima legislation of 1000ft, as well as in demanding manual flying situations in darkness and low visibility. Used in transponder applications, the project will give significantly increased reliability in altitude information for manual and automated Air Traffic Control systems. Aircraft Traffic Collision Avoidance Systems will also benefit from more accurate and reliable altitude information, which will allow the automated avoidance instructions to be more accurate and effective.
The HASTAC project main target has been to develop a new altimetry pressure transducer that should be better than reported state-of-the-art transducers in the market. The target was to achieve a demonstrated stability better than 0.01% (100ppm) maximum drift error per year. Previous state-of-the-art MEMS transducers were reported to be in the 0.02% range.
Accelerated tests performed in the HASTAC project, corresponding to more than 20 years of operation in room temperature conditions, indicate that the goal has been met. The statistical data is limited, and additional tests are still ongoing (March -08).
The four (4) transducers which have been on long term stability test, including more than 1000 thermal cycles, all indicate a 0.01% or less drift error per year. The documented results demonstrate a stability better than 0.01% (100 ppm)/year of full scale, which corresponds to a calibrated pressure range of -2000ft to 60,000ft (1150mbar – 50mbarA).